Uniquely modified anti-sense oligodeoxynucleotides (ODNs) targeted to the hepatitis B surface antigen transcript will be evaluated in a differentiated hepatoma cell line which supports the constituitive production of infectious Dane particles. Inhibition of surface antigen production will be monitored by analyzing aliquots of the media for hepatitis B surface antigen using a commercially available ELISA kit. ODN modifications to be examined will consist of alkyl side arms terminating in amino, cholesterol, or acridine groups. These arms will be introduced singly or in combination at 5', 3', and internal sites of the ODN. Selected ODNs will be complexed with an asialoorosomucoid-poly-L-lysine conjugate previously shown to promote receptor-mediated internalization of DNA in hepatocytes. The effect of this delivery system on the potency of the anti-sense effect and on the stability and cellular uptake of each ODN will be determined.